Dr. Robbins participates in the NCI/DOE project to study the thyroid effects of the nuclear power reactor accident in Chernobyl. The case- control study in Belarus has been completed and submitted for publication. The results clearly indicate that thyroid cancer cases have a higher thyroid radiation dose than controls matched for age, sex and route to diagnosis. The odds ratio is approximately six. Planning continues for the establishment of prospective cohort studies in Belarus and Ukraine to determine the risk coefficient for thyroid cancer development after exposure to radioiodines. Dr. Robbins participates with the NIH component of the interinstitutional Phase III evaluation of recombinant human TSH (rhTSH) for use in the management of patients treated for thyroid cancer. Initial findings, submitted for publication, indicate that rhTSH is effective in stimulating radioiodine uptake in tumor remnants or metastases while the patient remains euthyroid on thyroid hormone replacement. Current studies are investigating the effects of different dose schedules on the ability of rhTSH to induce tumor uptake as well as to induce an increase in serum thyroglobulin concentration, as required by the Food and Drug Administration prior to approval of the drug for clinical use.